A recent article in The Economist stated that “over the past 15 years air temperatures at the Earth’s surface have been flat while greenhouse-gas emissions have continued to soar.” The Economist went to great lengths to point out that “the mismatch between rising greenhouse-gas emissions and not-rising temperatures … does not mean global warming is a delusion.” But the piece was predictably lauded by climate skeptics as “further evidence” of the case against climate change.

Except that … it wasn’t.

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As The Economist piece itself pointed out, this wasn’t an argument that “global warming has ‘stopped.‘” The past two decades have been the hottest in recorded history; of the nine hottest years on record, eight have come since 2000. The question, though, is why the year-on-year/decade-on-decade increase appears to have been somewhat less in the past 10 to 15 years, given the ongoing increase in atmospheric greenhouse gas concentrations.

To which, there are several answers.

First, the smaller the temporal time scale, the more the short-term fluctuations, forcings and feedbacks – from aerosol emissions to La Nińa events – can distort the bigger picture. Over a longer scale, the evidence is increasing that the rate of warming is probably unprecedented in over 11,000 years.

Second, The Economist article, and the skeptic narrative that has absorbed it, focuses on what is known as “climate sensitivity,” which is how much surface warming the planet will experience in response to a doubling of atmospheric carbon dioxide concentrations relative to pre-Industrial Revolution levels. (Those pre-industrial levels were approximately 280 ppm; a doubling therefore would be roughly 560 ppm. Present levels are closing in on 397 ppm.)

VIDEO: Does Climate Change Threaten Coffee and Chocolate?

But, as climate blogger Joe Romm points out, climate sensitivity is but one factor in determining how much the planet will warm in the future; another hugely important one is the extent to which CO2 concentrations will actually increase, and present trends suggest they will blow past 560 ppm and wind up closer to 1,000 ppm. Additionally, while climate sensitivity estimates are greatly influenced by short-term feedbacks such as sea ice extent and water vapor, they do not factor in “slow” feedbacks, such as the release of methane as a result of tundra melt. Nor do they consider the non-linearity of such feedbacks – i.e. the fact that they may become significant relatively suddenly.

Third, the data referred to by The Economist suggest that climate sensitivity may be at the very low end of projected estimates of between 2 degrees Celsius and 4.5 degrees Celsius. If that indeed does prove to be the case, then that’s obviously good news. But, as Zeke Hausfather pointed out in a post at the Yale Forum on Climate Change and the Media: “A world with a relatively low climate sensitivity — say in the range of 2 °C — but with high emissions and with atmospheric concentrations three to four times those of pre-industrial levels is still probably a far different planet than the one we humans have become accustomed to. And it’s likely not one we would find nearly so hospitable.”

Finally, and most importantly, there is plenty of reason to suspect that climate sensitivity isn’t lower than expected; because, critically, The Economist article and the skeptic schadenfreude it spawned missed one hugely important point. Such discussions of climate sensitivity focus on surface warming of the planet; several recent studies have shown that in fact an increasing amount of warming is taking place beneath the surface, in the ocean depths.

Ninety percent of warming goes into heating, not the land or the atmosphere, but the ocean; two recent papers, in 2012 and earlier this year, showed that approximately 30 percent of recent ocean warming has been taken up by waters below depths of 700 meters (about 2,300 feet), where few measurements had previously taken place. That was reinforced by a European study, published earlier this week, which, according to Reuters, found “that the oceans took up more warmth from the air around 2000. That would help explain the slowdown in surface warming but would also suggest that the pause may be only temporary and brief … Lead author Virginie Guemas of the Catalan Institute of Climate Sciences in Barcelona said the hidden heat may return to the atmosphere in the next decade, stoking warming again.”

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Indeed, add together the net global heat content for the atmosphere, land, ice, surface ocean waters and deep ocean waters, and the total shows a continued, clear – and, in fact, rising – increase. As climate scientist and blogger Dana Nuccitelli, co-author of the aforementioned 2012 paper on ocean warming, points out, this means that “the slowed warming at the surface is only temporary, and consistent with (research indicating the existence of) ‘hiatus decades’ … The global warming end result will be the same, but the pattern of surface warming over time may be different than we expect …while many people wrongly believe global warming has stalled over the past 10–15 years, in reality that period is “the most sustained warming trend” in the past half century. Global warming has not paused, it has accelerated.”

Climate scientists have projected the North Pole will lose its summer ice cap after 2050 due to a warming climate melting sea ice. But a new study in the Geophysical Research Journal, led by James Overland of the National Oceanic and Atmospheric Administration, used three methods of projecting future ice cover and predicts summers with no ice much sooner.

"(A)ll three suggest nearly sea ice-free summers in the Arctic before the middle of this century," says study co-author Muyin Wang of NOAA's Joint Institute for the Study of Atmosphere and Ocean, in a statement.

The estimates produce ranges for an ice-free Arctic from 2020 to after 2040. "This paper should not be used as an argument against further modeling, but quite the opposite," says the study. "It is reasonable to conclude Arctic sea ice loss is very likely to occur in the first rather than the second half of the 21st Century, with a possibility of loss within a decade or two."

Disappearance of the summertime ice sheet will lead to cascading effects throughout the Arctic food chain for everything from plankton to fish to polar bears and other creatures living there. Geopolitical jousting over navigation and mining rights have already started, amid concerns about landslides due to melting permafrost and other land effects.

Sydney: Summer ice in the Antarctic is melting 10 times quicker than it was 600 years ago, with the most rapid melt occurring in the last 50 years, a joint Australian-British study showed Monday.

A research team from the Australian National University and the British Antarctic Survey drilled a 364-metre (1,194 feet) long ice core from James Ross Island in the continent's north to measure past temperatures in the area.

Visible layers in the ice core indicated periods when summer snow on the ice cap thawed and then refroze.

By measuring the thickness of these melt layers, the scientists were able to examine how the history of melting compared with changes in temperature at the ice core site over the last 1,000 years.

"We found that the coolest conditions on the Antarctic peninsula and the lowest amount of summer melt occurred around 600 years ago," said lead author Nerilie Abram of the ANU Research School of Earth Sciences.

"At that time, temperatures were around 1.6 Celsius lower than those recorded in the late 20th century and the amount of annual snowfall that melted and refroze was about 0.5 percent.

"Today, we see almost 10 times as much of the annual snowfall melting each year.

"Whilst temperatures at this site increased gradually in phases over many hundreds of years, most of the intensification of melting has happened since the mid-20th century," she added.

The research, published in the journal Nature Geoscience, is only the second reconstruction of past ice melt on the Antarctic continent.

Abram said it helped scientists gain more accurate projections about the direct and indirect contribution of Antarctica's ice shelves and glaciers to global sea level rise.

"What it means is that the Antarctic peninsula has warmed to a level where even small increases in temperature can now lead to a big increase in summer ice melt," she said.

"This has important implications for ice instability and sea level rise in a warming climate."

Robert Mulvaney, from the British Antarctic Survey, led the ice core drilling expedition and co-authored the paper.

"Having a record of previous melt intensity for the peninsula is particularly important because of the glacier retreat and ice shelf loss we are now seeing in the area," he said.

"Summer ice melt is a key process that is thought to have weakened ice shelves along the Antarctic peninsula leading to a succession of dramatic collapses, as well as speeding up glacier ice loss across the region over the last 50 years."

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Summer Ice Melt In Antarctica Is At The Highest Point In 1,0Mon Apr 15, 2013 7:38 pm

Summer Ice Melt In Antarctica Is At The Highest Point In 1,000 Years, Researchers Say

CANBERRA (Reuters) - The summer ice melt in parts of Antarctica is at its highest level in 1,000 years, Australian and British researchers reported on Monday, adding new evidence of the impact of global warming on sensitive Antarctic glaciers and ice shelves.

Researchers from the Australian National University and the British Antarctic Survey found data taken from an ice core also shows the summer ice melt has been 10 times more intense over the past 50 years compared with 600 years ago.

"It's definitely evidence that the climate and the environment is changing in this part of Antarctica," lead researcher Nerilie Abram said.

Abram and her team drilled a 364-metre (400-yard) deep ice core on James Ross Island, near the northern tip of the Antarctic Peninsula, to measure historical temperatures and compare them with summer ice melt levels in the area.

They found that, while the temperatures have gradually increased by 1.6 degrees Celsius (2.9 degrees Fahrenheit) over 600 years, the rate of ice melting has been most intense over the past 50 years.

That shows the ice melt can increase dramatically in climate terms once temperatures hit a tipping point.

"Once your climate is at that level where it is starting to go above zero degrees, the amount of melt that will happen is very sensitive to any further increase in temperature you may have," Abram said.

Robert Mulvaney, from the British Antarctic Survey, said the stronger ice melts are likely responsible for faster glacier ice loss and some of the dramatic collapses from the Antarctic ice shelf over the past 50 years.

Their research was published in the Nature Geoscience journal.

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Rising Sea Levels Could Be Slowed By Dealing With Four ShortMon Apr 15, 2013 10:59 pm

Of course, this approach will have absolutely no effect of dealing with the increasing acidification of the world's oceans and the resulting impact on critical marine life of the global ecosystem (think production of oxygen!).

Rising sea levels are expected to begin affecting many coastal cities in the decades to come, and researchers have been scrambling for a way to curb the impending flooding. An encouraging new study now states that curbing four key pollutants can effectively slow the rate of sea level rising by 25 to 50 percent.

The four pollutants - methane, tropospheric ozone, hydrofluorocarbons, and black carbon - are short-lived and cycle through the atmosphere far quicker than carbon dioxide.

"To avoid potentially dangerous sea level rise, we could cut emissions of short-lived pollutants even if we cannot immediately cut carbon dioxide emissions," says study author Aixue Hu from the National Center for Atmospheric Research (NCAR). "This new research shows that society can significantly reduce the threat to coastal cities if it moves quickly on a handful of pollutants."

A 2007 Intergovernmental Panel on Climate Change report stated that sea levels could rise 7 to 23 inches this century - an estimate many find too conservative. Contributors to this alarming rate include melting ice caps, which in turn are caused by rising global temperatures. Carbon dioxide, which can stay in the atmosphere for hundreds of years, has normally been singled out as the most damning greenhouse gas, but as the researchers point out, attacking shorter-term pollutants could buy us more time to deal with the larger issues.

"It is still not too late, by stabilizing carbon dioxide concentrations in the atmosphere and reducing emissions of shorter-lived pollutants, to lower the rate of warming and reduce sea level rise," says study leader Veerabhadran Ramanathan from Scripps University. "The large role of the shorter-lived pollutants is encouraging since technologies are available to drastically cut their emissions."

The study's authors believe that with proper implementation and use of technology currently available, countries can cut emissions of these four harmful pollutants by 30 to 60 percent over the next few decades.

Still, while these moves are definitely a step in the right direction, and do buy our society more time, it's important to keep our eyes on the prize, the scientists state.

"It must be remembered that carbon dioxide is still the most important factor in sea level rise over the long term," says NCAR scientist Warren Washington said.

The study, carried out with members from NCAR, Scripps, and Climate Central, can be read in the journal Nature Climate Change.

New Evidence of Climate Change: Earth's Current Warming Not Seen in 1400 Years

Catherine Griffin

There's now even more evidence that climate change exists. A new study reveals that Earth's climate has warmed more between 1971 and 2000 than at any other three-decade interval in the past 1,400 years. This period of warming, which continues to this day, actually reversed a natural cooling trend that lasted several hundred years beforehand.

The study involved more than 80 scientists from 24 different nations. Together, they analyzed climate data from tree rings, pollen, cave formations, ice cores, lake and ocean sediments and historical records from around the world. All of the data combined allowed the researchers to better understand the climate history of the planet, and examine exactly what trends have continued into the present day.

In particular, they noted that the Medieval Warm Period, which occurred from 950 to 1250, may not have been global. While parts of Europe and North America were fairly warm during this period, South America stayed fairly cold. This seems to refute the argument that humans are not responsible for modern day global warming and that, instead, the natural warming seen during the medieval ages is actually occurring today.

"If we went into another Medieval Warm Period again, that extra warmth would be added on top of warming from greenhouse gases," said Edward Cook, a co-author of the paper detailing the findings, in a press release. The current warming can, in fact, not be explained by a natural warming trend alone.

While the Medieval Warm Period stood out in terms of warming, it did not show a globally uniform pattern. Instead, the researchers found that temperatures varied less between continents in the same hemisphere than between hemispheres.

By 1500, temperatures dropped below the long-term average everywhere, though colder temperatures emerged several decades earlier in the Arctic, Europe and Asia. In fact, researchers found that the most consistent trend across all regions in the last 2,000 years was a long-term cooling, likely caused by a rise in volcanic activity, a decrease in solar irradiance, changes in land-surface vegetation and slow variations in Earth's orbit.

This cooling, though, began to taper off at the end of the 19th century--right about the time when industrialization began. The researchers found that warming in the 20th century was on average twice as large in the northern continents as it was in the Southern Hemisphere.

Yet what is most interesting are the most recent climate events. The study discovered that Europe's 2003 heat wave and drought, which killed an estimated 70,000 people, actually occurred during the region's hottest summer of the last 2,000 years.

"Summer temperatures were intense that year and accompanied by a lack of rain and very dry soil conditions over much of Europe," said Jason Smerdon, a study co-author, in a press release. The researchers estimate that global warming was just one of several of factors that contributed to the high temperatures.

The study has allowed scientists to get a better view of exactly what has influenced our climate over the past several thousand years. It could also give them the opportunity to better study natural cooling and warming trends.

Connect The Dots On Climate Change: The Tangible Effects Of A Warming World

The Huffington Post | By James Gerken

Climate change means drastic and long-term effects like rising sea levels and the increased likelihood of extreme weather events. But across the world, we are already witnessing the consequences of a warming world.

In the U.S., climate change means that allergies are getting worse as pollen counts increase, and some of your favorite foods -- from apples to oysters to coffee and wine -- are also in jeopardy. Warmer winters in northern latitudes also mean worsening conditions for outdoor sports like hockey, dog sled racing and skiing. There is also increased pressure on an already fragile water supply.

On a global level, sea level rise poses an existential threat to low-lying nations in the Pacific, while in Africa, climate change is making droughts and deadly famines more likely.

Dramatic change is already evident in the Arctic. After record sea ice melt in 2012, NOAA research shows that the Arctic will see ice-free summers by 2050, if not within the next decade or two. It has been suggested that "what happens in the Arctic doesn’t stay in the Arctic," and melting there may contribute to more extreme weather at moderate latitudes.

Scientists are nearly unanimous in their findings that climate change is both real and manmade. Research has shown that current human activities, like the burning of fossil fuels, are inevitably going to cause atmospheric warming and sea level rise for at least another 1,000 years.

International leaders have stressed the imperative to address climate change and warned that the global development of low-carbon energy may be happening too slowly.

Learn about some of the most evident effects of climate change in the slideshow below.

Note, go to original article (link above) to see slide show of significant environmental changes due to climate change.

Waters off Northeast US coast unusually warm, says NOAA Sea surface temperatures on the Northeast US Continental Shelf reached the highest recorded in 150 years, says an advisory issued by the National Oceanic and Atmospheric Administration.

By Eoin O'Carroll

From North Carolina to Maine, the waters have been unusually warm lately.

This is according to the National Oceanic and Atmospheric Administration's Northeast Fisheries Science Center, which issued an advisory today noting that sea surface temperatures in the Northeast Shelf Large Marine Ecosystem during the second half of 2012 were the highest recorded in 150 years.

According to the advisory, sea surface temperatures in this region, which extends from Cape Hatteras to the Gulf of Maine and outward to the boundary of the continental shelf, increased dramatically to reach a record 57.2 degrees Fahrenheit, beating a previous record high in 1951. The average temperature over the past three decades has been typically lower than 54.3 degrees Fahrenheit.

The temperatures were recorded via satellite and ship-board measurements. Historical measurements, based on ship-board thermometers, date back to 1854. According to NOAA, the warming was the greatest increase on record, and one of only five instances when the temperature has changed by more than 1.8 degrees Fahrenheit. These drastic changes have not been noted elsewhere in the ocean basin, although in recent years global sea surface temperatures have been the highest on record.

The warmer ocean temperatures might be good news for beachgoers in the Northeast, but they could also disrupt ecosystems, along with the livelihoods that depend on them. The report notes that black sea bass, summer flounder, longfin squid, and butterfish have been migrating northeastward. Lobsters are migrating too, but at a slower rate.

“What these latest findings mean for the Northeast Shelf ecosystem and its marine life is unknown,” Fogarty said. “What is known is that the ecosystem is changing, and we need to continue monitoring and adapting to these changes.”

Global warming is causing plants to emit chemicals that lead to climate-cooling clouds, say researcher in a new study. The effect of these climate-cooling clouds would be negligible in places where humans are already changing the atmosphere say scientists. However, in more remote areas of the planet, their effects could slow the effects of global warming-though not by much scientists warn.

"It's not that much," Pauli Paasonen reportedly said. Paasonen, of the University of Helsinki in Finland and one of the authors of the new study, did point out however that understanding the plant emissions-and their role in global warming-brings scientists one more step closer to understanding the roles of small particles -- called aerosols -- in future climate change. In their paper, the scientists also point out that the release of the plant emissions is one of the very few "negative" feedbacks to climate change.

Most feedbacks to climate change are "positive," meaning they tend to make the warming worse. For example, melting sea ice allows sunlight to warm seawater; permafrost melts, releases carbon dioxide, and adds to the overall greenhouse gas problem.

Paasonen and his colleagues came to their conclusions about the plant emissions after gathering and analyzing temperature and aerosol data from site found throughout the globe. The sites the team visited were found in both the mid and high-latitudes sites, both clean and polluted. The scientists found that plants increased their production of climate cooling gases as the temperature increased,, probably the release of these sticky compounds make particles large enough for water to condense on.

The implications of the work could significant depending on how effective the plant gases are at cooling an area. Scientists stress however that in heavily polluted areas there are so many aerosols found in the air that the plant contributions make no difference.

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New research determines how cirrus clouds formFri May 10, 2013 3:26 pm

What a surprise...MIT and NOAA scientists find that METALLIC AEROSOLS provide condensation nuclei for the formation of cirrus clouds. Must read the source article to see if ANY EFFORT IS MADE TO IDENTIFY THE SOURCE OF THESE METALLIC AEROSOLS...or is this just another group of "Esteemed Scientists" feeding at the trough.

Cirrus clouds, characterized by their thin, wispy strands, influence global climate due to their ability to both absorb incoming radiation as well as trap heat. Scientists have focused on studying these light vapor masses in recent years as a way to examine and help predict future climate patterns.

In a study funded by NASA and the National Science Foundation, an interdisciplinary team from MIT, NOAA (National Oceanic and Atmospheric Administration), among others, sampled cirrus clouds from research aircraft, collecting particles over nine years and analyzing them. The study, published in Science magazine this week, found that the majority of cloud particles freeze (nucleate) around two types of seeds: mineral dust and metallic aerosols.

“We think we’re really looking at the seed, the nucleus of these ice crystals,” Dan Cziczo, an associate professor of atmospheric chemistry at MIT, explained to Phys.org. “These results are going to allow us to better understand the climatic implications of these clouds in the future.”

The team accomplished four flight missions over the nine years between 2002-2011 in North and Central America, where cirrus clouds typically form. Before takeoff, the team examined weather forecasts to determine the best area for hunting a cloud. “More often than not, the forecast is solid, and it’s up to the pilot to hit a cloud,” Cziczo says. “If they find a good spot, they can call back on a satellite phone and tell us if they’re inside a cloud, and how thick it is.” From there, the plane takes in ice particles which thaw and were then examined by the team. A particle collector and a mass spectrometer were mounted to the nose of the plane for this purpose.

What the team discovered was that over 60 percent of the particles consisted of mineral dust blown into the atmosphere, pointing to a significant human impact.

While many lab experiments have found evidence of biological particles and black carbon (the latter emitted from automobiles), the current study found little evidence of these in the clouds. Research team participant Karl Froyd, of NOAA’s Earth System Research Laboratory, expressed that this information is just as significant as what was found, for the purposes of creating accurate climate change models.

“There’s been a lot of research efforts spent on looking at how these particle types freeze under various conditions,” Froyd explained. “Our message is that you can ignore those, and can instead look at mineral dust as the dominant driving force for the formation of this type of cloud.”

Formation of cirrus clouds depends upon the availability of ice nuclei to begin condensation of atmospheric water vapor. While it is known that only a small fraction of atmospheric aerosols are efficient ice nuclei, the critical ingredients that make those aerosols so effective has not been established. We have determined in situ the composition of the residual particles within cirrus crystals after the ice was sublimated. Our results demonstrate that mineral dust and metallic particles are the dominant source of residual particles, while sulfate/organic particles are underrepresented and elemental carbon and biological material are essentially absent. Further, composition analysis combined with relative humidity measurements suggest heterogeneous freezing was the dominant formation mechanism of these clouds.

The last time CO2 was regularly above 400ppm was about 3-5 million years ago - before modern humans existed.

The climate back then was also considerably warmer than it is today, according to scientists.

Carbon dioxide is regarded as the most important of the manmade greenhouse gases, a product principally of burning fossil fuels such as coal, oil and gas.

The usual trend seen at the volcano is for the CO2 concentration to rise in winter months and then to fall back as the northern hemisphere growing season kicks in and pulls some of the gas out of the atmosphere.

This means the number can be expected to decline by a few ppm below 400 in the coming weeks. But the long-term trend is upwards.

When the famous Charles Keeling began recording CO2 concentrations at the volcano in 1958, they were around 315 ppm (that is 315 molecules of CO2 for every one million molecules in the air). Every year since then, the curve has squiggled resolutely higher.

To determine CO2 levels before the introduction of modern stations, scientists must use so-called proxy measurements.

These include studying the bubbles of air trapped in Antarctic ice. The longest of these records goes back 800,000 years, and suggests CO2 held steady over this longer period at between 200ppm and 300ppm.

More than half of common plant species and a third of animals could see a serious decline in their habitat range because of climate change.

New research suggests that biodiversity around the globe will be significantly impacted if temperatures rise more than 2C.

But the scientists say that the losses can be reduced if rapid action is taken to curb greenhouse gases.

The paper is published in the journal, Nature Climate Change.

An international team of researchers looked at the impacts of rising temperatures on nearly 50,000 common species of plants and animals.

They looked at both temperature and rainfall records for the habitats that these species now live in and mapped the areas that would remain suitable for them under a number of different climate change scenarios.

The scientists projected that if no significant efforts were made to limit greenhouse gas emissions, 2100 global temperatures would be 4C above pre-industrial levels.

In this model, some 34% of animal species and 57% of plants would lose more than half of their current habitat ranges.

More than half of common plant species and a third of animals could see a serious decline in their habitat range.

Science Recorder | Ellen Miller

A new study published in Nature Climate Change suggests that if nothing is done to curb climate change, the impact on animal and plant life could be catastrophic.

The study, which comprises of researchers from the U.K., Columbia and Australia, examined the impact of climate change (specifically rising temperature) on nearly 50, 000 different species.

The team carried out climate modeling and examined three main factors: climate sensitivity, ocean mixing and climate-carbon feedback that amplifies the temperature. By mapping the areas that would remain suitable for species habitation scientists were able to determine that there would be a great habitat loss unless mitigating factors emerge.

According to the report, global warming will destroy over half the habitat of plant life and a third of the habitat of animal life, a transition that may occur as a tipping point or over long periods. Temperatures are predicted to rise seven degrees Fahrenheit by 2100 due to global warming, according the Intergovernmental Panel on Climate Change (IPCC). The rise in temperature is largely due to burning fossil fuels, which retain heat and warm the atmosphere. Over the past century, global temperatures have risen about 1.4 degrees Fahrenheit, according data presented by the National Academy of Sciences. If this temperature rise happens at the rate predicated, large range contractions can be expected among common and widespread species.

The changes predicted by the model would likely lead to the extinction of some 34 percent of animal species and 57 percent of plant species, say scientists. The reason for the massive decline, according to the report, is largely due to the rapid change in temperature, which many species will struggle to adapt to over the course of just a few years.

“Our research predicts that climate change will greatly reduce the diversity of even very common species found in most parts of the world. This loss of global-scale biodiversity would significantly impoverish the biosphere and the ecosystem services it provides,” says Rachel Warren, of the University of East Anglia and a lead author of the study.

The team notes that the rapid change would have major ramifications for humans. By losing nearly 50 percent of plant and animal diversity, diseases could spread far more rapidly than before, and remedies derived from plants and animals will likely be far more limited. More concerning, scientists noted that it is nearly impossible to predict the fallout from such a change, which is unprecedented in human history. In addition, world food supplies could dwindle, and water and air quality may be greatly reduced, according to researchers.

“The terrifying loss of biodiversity predicted by this study shows that climate chaos will fundamentally transform our planet,” Shaye Wolf of the Center for Biological Diversity, a conservation group, says in a statement on the study obtained by USA Today. “We need to cut emissions now, before our ecosystems suffer catastrophic damage.”

While the predictions presented by the team are hardly cheerful, there was one silver lining: The research team asserts that if greenhouse gases are cut rapidly, the loss can be mitigated significantly. If global emissions peak in 2016 and temperatures only rise by 3.6 degrees Fahrenheit, the losses can be decreased by 60 percent.

While the figures are stunning, it remains unclear whether policy makers worldwide will take action. A number of international conferences, thus far, have failed to put forward a replacement for the Kyoto Protocol, which sought to limit the emissions of greenhouse gases. While a number of countries, including the U.S., have sought to limit the emissions of global warming gases, figures show concentrations of carbon dioxide continuing to grow. A recent report, in fact, shows carbon dioxide emissions topping nearly 400 ppm, a significant mark, according to climate change analysts.

A warming climate is melting the glaciers of Mount Everest, shrinking the frozen cloak of Earth’s highest peak by 13% in the last 50 years, researchers have found.

Rocks and natural debris previously covered by snow are appearing now as the snow line has retreated 590 feet, according to Sudeep Thakuri, a University of Milan scientist who led the research.

The pessimistic view of Earth’s tallest peak was presented during a meeting Tuesday of the American Geophysical Union in Cancun, Mexico.

Researchers said they believe the observed changes could be due to human-generated greenhouse gases altering global climate, although their research has not established a firm connection.

The team reconstructed the glacial history of the area using satellite imagery and topographic maps of Everest and the surrounding 713-square-mile Sagarmatha National Park. Their statistical analysis shows that the majority of the glaciers in the national park are retreating at an increasing rate, Thakuri said.

Small glaciers of less than a square kilometer (about 247 acres), are vanishing fastest, registering a 43% decline in surface area since the 1960s.

Average temperatures have risen about 1 degree Fahrenheit since 1992, according data from the Nepal Climate Observatory stations and Nepal’s Department of Hydrology and Meteorology, the researchers found. Since 1992, precipitation has declined nearly four inches during the pre-monsoon and winter months, they found.

“The Himalayan glaciers and ice caps are considered a water tower for Asia since they store and supply water downstream during the dry season,” said Thakuri. “Downstream populations are dependent on the melt water for agriculture, drinking and power production.”

The topic of glacial melt in the Himalayas has been controversial. Initial reports by the Intergovernmental Panel on Climate Change predicted glaciers in the region would disappear by 2035. Subsequent analysis by the Gravity Recovery and Climate Experiment (GRACE) satellite mission showed that the melt was one-tenth the reported rate, and that some areas were experiencing growth, particularly in the Tibetan plateau.

Research published last year, however, showed that glaciers have been retreating over a 30-year period on the Tibetan plateau. It also showed that areas that depend on snow during regional monsoon seasons are particularly vulnerable to small rises in temperature.

The plateau is of concern because it is the ultimate source of drinking and irrigation water for more than 1 billion people in Asia.

Public opinion on the topic of climate change is notoriously fickle, changing -- quite literally sometimes -- with the weather. The latest bit of evidence on this: Yale's April 2013 climate change survey, which found, among other things, that Americans' conviction that global warming is happening had dropped by seven points, to 63 percent, over the preceding six months. The decline, the authors surmised, was most likely due to "the cold winter of 2012-13 and an unusually cold March just before the survey was conducted."

People and surveys being what they are, these numbers tend to jump around a bit from year to year. At the same time, 49 percent is nearly half the country, so it wouldn't be excessively cheerful (would it?) to note that half of the American public is more or less in harmony with basic science -- at least as it relates to climate change. Given that roughly the same number of Americans flatly reject evolution, the climate numbers represent a comparative bounty of enlightenment.

That's not something you hear very often when it comes to surveys of Americans. Delving deeper into the textbooks, for instance, another recent study showed that less than half of population was clear on whether atoms are smaller than electrons, or whether lasers work by focusing sound waves. In this light (ahem), the larger consensus on global warming is notable. (Answers on atoms and lasers appear at the end of this column.)

But a far more troubling metric from Yale's latest poll suggests that only 42 percent of Americans believe that most scientists think global warming is happening. A full 33 percent of respondents are convinced that there remains "widespread disagreement" among scientists on this question.This is a problem -- both because it is so at odds with reality, and because it likely helps prevent more Americans from recognizing and accepting some pretty straightforward scientific realities.

It is this reason that prompted a team of researchers to painstakingly comb through the abstracts of more than 12,000 scientific articles published between 1991 and 2011 to determine just how much scientific agreement exists on the subject of climate change, and humanity's role in driving it. The team was led by John Cook, a Climate Communication Fellow for the Global Change Institute at the University of Queensland and the founder of the climate change education web site SkepticalScience.com.

The results, published Thursday in the journal Environmental Research Letters, were clear: of the more than 4,000 abstracts that had anything to say about human-driven climate change, 97 percent endorsed the notion. A little less than 3 percent either rejected the idea or remained undecided.

"There is a gaping chasm between the actual consensus and the public perception," Cook said in a statement accompanying the study's release. "It's staggering given the evidence for consensus that less than half of the general public think scientists agree that humans are causing global warming. This is significant because when people understand that scientists agree on global warming, they're more likely to support policies that take action on it."

In a follow-up email exchange, Cook said that the evidence for consensus on the topic among individual scientists was even stronger, given that more researchers were listed as co-authors on papers endorsing the idea of human-driven climate change -- technically called "anthropogenic global warming," or AGW for short -- than on papers that rejected it.

"Consequently," Cook said, "among the 10,000 scientists who had expressed a position on AGW in the peer-reviewed literature, 98.4 percent endorsed the consensus."

The study, which is also outlined in detail (and with colorful slides) at The Consensus Project, is the latest in a long line of meta-analyses seeking to debunk the relentless and apparently potent talking points of naysayers who argue that scientists continue to disagree on the matter. Last year, the free-market and right-leaning Heartland Institute financed a series of billboards in Chicago comparing those who understand and accept the basic science on global warming to unsavory characters like convicted murderer Charles Manson, Cuban dictator Fidel Castro and the Unabomber, Ted Kaczynski.

"The point is that believing in global warming is not 'mainstream,' smart, or sophisticated," the organization wrote at the time. "In fact, it is just the opposite of those things."

Studies like Cook's, which revisits a well known and similarly conducted 2004 review of the scientific literature by Naomi Oreskes at the University of California, San Diego, provide clear evidence that messages like Heartland's -- besides being rather boorish and odd -- are, in the end, bunkum. Scientists are no more divided on the basic mechanics of the greenhouse effect than they are on questions of evolution (sorry folks) or other elementary concepts.

Sure, there's ample room for debate on the particulars: How hot will the planet get? How quickly? How will our various ecosystems, from forests and oceans to vast tracts of tundra and polar ice, respond to rising temperatures, and how will these responses feed, in turn, into the incredibly dynamic and interactive machinery of our climate? And then based on all this, what the hell should we do about it? These are all questions without precise answers, and they are providing rich and important territory for scientific investigation as well as social, political and economic soul searching.

What's not a matter of debate, however, is that human beings are saturating the atmosphere with volumes of carbon dioxide -- mostly arising from the burning of fossil fuels -- at an unprecedented rate. That's trapping heat and driving up average surface temperatures across the planet, which in turn is spurring regional changes in weather that we are only now beginning to understand. On these points, virtually all climate scientists agree.

A famous 2009 study published in the Proceedings of the National Academy of Sciences came at the question of scientific consensus from an entirely different angle, but arrived at nearly identical results. That study reviewed public statements made by scientists of any kind about anthropogenic global warming, and then identified which of those scientists had published peer-reviewed climate research -- this as a way of weeding out those who publicly reject human-driven global warming but have no formal expertise or training in climate science, like these folks.

Among the nearly 1,000 most actively published climate scientists, that analysis found that between 97 and 98 percent supported the basic tenets of human-driven climate change -- a very similar result to the one published Thursday by Cook and his colleagues.

"We want our scientists to answer questions for us, and there are lots of exciting questions in climate science," said one of Cook's co-authors, Mark Richardson of Britain's University of Reading, in a statement accompanying the release of the study. "We found over 4,000 studies written by 10,000 scientists that discussed whether recent warming is mostly man-made," Richardson said, "and 97 percent answered 'yes.'

We can't possibly expect to agree on everything. Should there be subsidies for cleaner forms of energy, or a stiff tax on carbon pollution, or both? Or do we simply wait it out in the hopes that necessity -- in the form of rising seas, more destructive storms, choking droughts and other climate-related freakishness -- will drive invention and save the day? For my money, an ounce of early prevention would seem worth a ton of cure further down the line, but I understand the differing opinions.

But what's not a matter of debate -- and indeed, what is a virtual certainty among scientists -- is that we've got a problem on our hands, and we're going to have to deal with it sooner or later.

So if you count yourself among the 49 percent of Americans who believe that climate change is happening, and that we're playing a key role in it, give yourself a gold star. The planet's best and brightest scientific minds agree with you.

And if you weren't sure whether electrons were smaller than atoms (they are), or that lasers work by focusing light, not sound, well, take heart: Scientists have got your back. See the science and technology survey published last month by the Pew Research Center and Smithsonian magazine for more.